The invention relates generally to inspection systems and, particularly, to a system for acquiring images of articles, such as glass containers, on a moving conveyor for use in inspecting the articles.
Container molding machines, referred to in the industry as individual section (IS) machines, are used to form containers, such as glass bottles and jars. Typically, an IS machine has a number of sections, each section having multiple cavities or molds, in which molten glass is formed into the desired container shape. After forming, a conveyor or the like moves the containers through a lehr which anneals the glass by subjecting the containers to stress-relieving temperatures. During the forming and annealing process, various defects (e.g., improper annealing, embedded foreign objects, variations in glass density, or other anomalies) may occur. An accurate and reliable inspection system is needed for identifying containers with defects and for inspecting the containers' profiles.
Further, many of these defects may be corrected during the manufacturing process to minimize the number of defective containers formed by the molding machine. Therefore, such an inspection system which provides feedback to the container molding machine and/or the lehr is desired to correct defects in subsequently formed containers.
Conventional inspection systems include line scan cameras for generating one-dimensional images of a container as it moves past the cameras. In other words, the cameras capture line images. Unfortunately, such cameras operate at a fixed speed and, thus, the line images are affected by the speed of the container. In other words, the images appear compressed or expanding depending on the container's speed. Further, the images of the container are processed line-by-line.
For these reasons, an inspection system which operates as a function of container speed to prevent imaging errors and which acquires two-dimensional images for processing to detect defects or obtain a container profile is desired.